int
get_option_uint8(uint8_t *i, const struct dhcp_message *dhcp, uint8_t option)
{
const uint8_t *p = get_option_raw(dhcp, option);
if (!p)
return -1;
*i = *(p);
return 0;
}
int
get_option_addr32(uint32_t *a, const struct dhcp_message *dhcp, uint8_t option)
{
const uint8_t *p = get_option_raw(dhcp, option);
if (!p)
return -1;
memcpy(a, p, sizeof(*a));
return 0;
}
int
get_option_addr(struct in_addr *a, const struct dhcp_message *dhcp,
uint8_t option)
{
const uint8_t *p = get_option_raw(dhcp, option);
if (!p)
return -1;
memcpy(&a->s_addr, p, sizeof(a->s_addr));
return 0;
}
int
get_option_uint16(uint16_t *i, const struct dhcp_message *dhcp, uint8_t option)
{
const uint8_t *p = get_option_raw(dhcp, option);
uint16_t d;
if (!p)
return -1;
memcpy(&d, p, sizeof(d));
*i = ntohs(d);
return 0;
}
ssize_t
configure_env(char **env, const char *prefix, const struct dhcp_message *dhcp,
const struct options *options)
{
unsigned int i;
const uint8_t *p;
int pl;
struct in_addr addr;
struct in_addr net;
struct in_addr brd;
char *val, *v;
const struct dhcp_opt *opt;
ssize_t len, e = 0;
char **ep;
char cidr[4];
uint8_t overl = 0;
get_option_uint8(&overl, dhcp, DHO_OPTIONSOVERLOADED);
if (!env) {
for (opt = dhcp_opts; opt->option; opt++) {
if (!opt->var)
continue;
if (has_option_mask(options->nomask, opt->option))
continue;
if (get_option_raw(dhcp, opt->option))
e++;
}
if (dhcp->yiaddr)
e += 5;
if (*dhcp->bootfile && !(overl & 1))
e++;
if (*dhcp->servername && !(overl & 2))
e++;
return e;
}
ep = env;
if (dhcp->yiaddr) {
/* Set some useful variables that we derive from the DHCP
* message but are not necessarily in the options */
addr.s_addr = dhcp->yiaddr;
setvar(&ep, prefix, "ip_address", inet_ntoa(addr));
if (get_option_addr(&net, dhcp, DHO_SUBNETMASK) == -1) {
net.s_addr = get_netmask(addr.s_addr);
setvar(&ep, prefix, "subnet_mask", inet_ntoa(net));
}
i = inet_ntocidr(net);
snprintf(cidr, sizeof(cidr), "%d", inet_ntocidr(net));
setvar(&ep, prefix, "subnet_cidr", cidr);
if (get_option_addr(&brd, dhcp, DHO_BROADCAST) == -1) {
brd.s_addr = addr.s_addr | ~net.s_addr;
setvar(&ep, prefix, "broadcast_address", inet_ntoa(brd));
}
addr.s_addr = dhcp->yiaddr & net.s_addr;
setvar(&ep, prefix, "network_number", inet_ntoa(addr));
}
if (*dhcp->bootfile && !(overl & 1))
setvar(&ep, prefix, "filename", (const char *)dhcp->bootfile);
if (*dhcp->servername && !(overl & 2))
setvar(&ep, prefix, "server_name", (const char *)dhcp->servername);
for (opt = dhcp_opts; opt->option; opt++) {
if (!opt->var)
continue;
if (has_option_mask(options->nomask, opt->option))
continue;
val = NULL;
p = get_option(dhcp, opt->option, &pl, NULL);
if (!p)
continue;
/* We only want the FQDN name */
if (opt->option == DHO_FQDN) {
p += 3;
pl -= 3;
}
len = print_option(NULL, 0, opt->type, pl, p);
if (len < 0)
return -1;
e = strlen(prefix) + strlen(opt->var) + len + 4;
v = val = *ep++ = xmalloc(e);
v += snprintf(val, e, "%s_%s=", prefix, opt->var);
if (len != 0)
print_option(v, len, opt->type, pl, p);
}
return ep - env;
}
